Fuel injection pump for diesel motors



Jan. 10, 1939. s. .n-:NclcK FUEL INJECTION PUMP FOR DIESEL MOTORS Filed Feb. 18, 1935 4 Sheets-Sheet l INVENTORA .Sz'EPHfNLE'NcIL'K Jan. 10, '5l JENC|CK 2,143,698

FUEL INJECTION PUMP FOR DIESEL MOTORS Filed Feb. 18, 1955 4 Sheets-Sheet 2 14 Eggs.

INVENTOR. 1g STEPHEN JLwcmK.

ATTORNEYS.

Jan.- 10, 1939. s JENCICK 2,143,698

FUEL INJECTION PUMP` FOR DIESEL MOTORS Filed Feb. 18, 1955 4 Sheets-Sheet 3 INVENTOR. Z5 STEPHEN J-Ncfcx.

ATTORNEYS,

Jan. l0, 1939. s JEN|CK 2,143,698

FUEL INJECTION PUMP FOB DIESEL MOTORS Filed Feb. 18, 1955 4 Sheets-Sheet 4 v INVENTOR. STEPHEN JENUIGK.

A TTORNEYS Patented Jan.l 10, 1939 PATENT OFFICE FUEL INJECTION PUMP FOR DIESEL 4 MOTOR Stephen Jencick, Chagrin Falls, Ohio Application February;` 18, 1935, Serial No. I7,018

6 clainis.

This invention relates to an improved fuel injecton pump for a Diesel motor.

The object of this invention is to devise a fuel injection pump that has a simple, compact and elcient structure and arrangement of operating parts including an improved means for varying the quantity of fuel injected and for adjusting the timing in conjunction therewith.

Other and more specific objects will appear from the following description and claims when considered together with the accompanying drawings. 1

Fig. 1 is a vertical sectional view ofmy improved device, taken on line I I of Fig. 2;

Fig. 2 is a top plan view thereof;

Fig. 3 is an elevation thereof;

Figs. 4, 5, and 6 are views taken on lines 4 4, 5 5, and 6 6, respectively, of Fig. 1;

Fig. '7 shows in elevation some of the parts, including the 4metering cam, shown in section in Fig. 4;

Fig. 8 is an elevation of the cam for varying the length of stroke of the plungers and for ensuring their return movement;

Fig. 9 is an elevation of the injection cam Fig. 10 is a plan view of the adjusting means for the metering cam;

Fig. 11 is an elevation of the same;

Fig. 12 is a plan view of the metering cam;

Fig. 13 is an elevation of the same; l

Fig. 14 is an elevation of the injection and return cams together; and

Fig. 15 is a View taken on line I5 I5 of Fig. 14.

In the present illustration and description, it is taken for granted that the manner of assembly and the connections of the fuel injection device with the other parts of the motor will be readily understood by those who are familiar with the art to which this invention relates, and the disclosure of the injection device itself is therefore suicient for present purposes.

The present injection device may be recognized as a substantially self-contained unit with suitable means for convenient connection to the other parts of the motor.' This device occupies upright position when in assembly and the general axis of the device is vertically disposed, so far as the arrangement and operation of the parts are concerned.

The body of the device, in a general way, comprises the lower casing i and the plunger housing 2 between which there is arranged aplunger guide 3, to be more fully described.

The oil pump 4, which is operated by the drive shaft 5, has connection through the tube 6 with (Cl. 12S-139) the oil reservoir 1 in the upperpart of the plunger housing 2, this reservoir being closed by the screw cap 8.

'Ihe oil is adapted to be drawn from the reservoir I through the restricted passages 9, past the ball checkvalves IIJ and into the chambers of the reciprocatable plungers II. There will be as many plungers II as there are cylinders in the engine, there being illustrated in the present case a six cylinder engine; and each plunger is provided with an individual passage 9 and check valve IU. The check valve Ill in each instance is adapted to be opened by the suction of the plunger II and is seated by its coil spring indicated.

Each plunger cylinder is also provided with a restricted discharge passage I2 whichjs adapted to be closed by the ball check valve I3 which is normally closed by its spring, as indicated in the drawings. The check valve I3 is adapted to be opened by the pressure caused by upward discharging movement of the plunger, and the plunger chamber is then in communication with the tubing I4 which has suitable sealed connection to the plunger housing, as indicated in the drawings, and which leads to a suitable spray nozzle (not shown) and the corresponding cylinder of the engine, as will be understood.

From the above description, it will be seen that downward movement of the plunger II will suck the fuel from the reservoir 'I past the check valve' I0 and into the plunger chamber whence. it will then be forced under pressure by upward discharging movement of the plunger out pastthe check valve I3 and through the tubing I4 to the spray nozzle and the engine cylinder. All the plungers operate in the same manner and in properly timed sequence, as will be readily understood.

The plungers II all have a tight t in their chambers, with enough freedom for movement in the manner intended, and the fuel is forced by the plungers out through a suitably restricted orifice so as to` function in the manner intended.

Each plunger II is provided with a sleeve I5 The pin I'I, in each instance, has its.

tending annular cam portion I8a of the injection cam I8 which is located in the lower casing I. The cam i8 has a central, upwardly extending neck portion I8b up through which extends the cam is connected to the cam shaft by means of f the horizontally disposed pin 28 which extends through the vertical slots 25 in the wall of the hollowed-out cam shaft and the inclined or cam slots 26 in the hollow neck portion I8b of the cam, slots 28 being oppositely inclined, as viewed in the drawings.

Thus, it will be seen that operation of the cam shaft will cause the cam to rotate and to raise the plungers II in succession so as to pump fuel from the reservoir to the cylinders of the engine.

The timing of the plunger action can be retarded or advanced by rotatably adjusting the injection cam and this is effected by vertical adjustment of pin 24 in the inclined slots 26 of the` injection cam. The pin 24 may be raised or lowered by means of the rod 21 which is capable of such movementwithin the hollowed-out cam shaft I9. 'I'he upper end of the rod 21 has extending therethrough the pin 28 which is permitted to movegup or down with the rod 21 by the ,vertically disposed slots I9a in the opposite sides of the hollowed-out cam shaft I9. Any suitable means may be provided for retaining shaft I9 a'..ially in proper place, as for instance collar means affixed to the shaft and engaged by the inner race of the ball hearing means.

The ends of pin 28 seat in the race provided betweenV the metering cam 29 and its companion ring member 30 which is secured therewithin by means of counter-sunk screws, this metering cam mechanism surrounding the upper end of the cam shaft I9. 'The metering cam 29 is provided with three equi-spaced inclined cam slots in the outer face thereof for co-operation with-the correspondingly spaced stationary pins 3| projecting in through thewall of the plunger housing. The purpose of this mechanism is to convert a turning adjustment of the metering cam combination into the vertical movement of the rod 21, as above referred to, for eifecting rotary adjustment of theplunger cam, as above explained.

The turning adjustment of the metering cam, above referred to, is effected by manipulation of the crank 32 which has an operating extension to the panel board where it is easily accessible by the operator and which turns the shaft 33 upon which is fixed the depending pin 34. This pin has engagement within a recess cut out in the top of the member 30, the effect being to cause turning of the metering cam one direction or the other about its vertical axis as a result of the turning of the crank shaft 33 in one direc'- tion or the other.

Thus,it will be seen that by manipulating crank V32, the metering cam will be turned and, by virtue of the pins 3I, will be given a vertical adjustment with the rod 21. ISuch movement of rod 21 will cause the pin 2G to have vertical active engagement with the cam slots 26 of the injection cam which thereby is given rotatable adjustment. The eiect of such adjustment of the .cam I8 is to vary the timing of the operation of the plungers by the cam.

The manipulation of the crank 32, as above described, isV effective also in producing an adjustment of the length of stroke of the plungers, this adjustment being effected simultaneously with the adjustment of the timing above referred to.

The ends of pin 2li are mounted in the lateral slots 2118L in the return cam 35 in the outer side of which there is formed a cam slot 35H, the inner ends of plunger pins I1 engaging in this cam slot 35B.

The cam 35 surrounds and has spline engagement with the neck of the injection cam I3 so as to be rotatably adjustable therewith as a unit and to be ladjustable vertically independently thereof, the injection cam being capable of only rotatable adjustment.

The purpose of the vertical adjustment of the cam 35 is to vary the vertical position of the plunger pins I1 and hence the plungers themselves with respect to the injection cam I8 and thereby vary the length of stroke of the plungers. This adjustment is in co-ordination with the variation in the timing of the plunger operation above referred to. That is, as the length of stroke is increased and the quantity of fuel injection correspondingly increased, the timing will be advanced, and vice versa.

As will be readily understood, the length of stroke of the plungers will be increased by lowering the cam 35 and the plungers so as to thereby increase the effect of the cam I8 upon the plungers.

The cam portion I8a of the injection cam extends approximately about the cam while the remaining portion of the cam'is at. Likewise, the upper corresponding portion of cam gr'oove 35a of the return cam extends approximately 110 thereabout while the remaining portion thereof is at. The bottom part of cam groove 35a vis fiat throughout its entire extent. That portion of cam groove 35B which corresponds to cam portion I8a is of greater height than cam portion I8, so as to permit vertical adjustment of the plungers and thereby vary the length of stroke thereof. Thus, the plungers can be lowered so as to lower their pins I1 more or less with respect to cam portion I8El and the increased height of the cam groove 35a will permit the full upward movement of the pins I'I for the length of stroke for which the cam 35 has been set. When the cam 35 has been set for the greatest possible length of stroke of the plungers, the pins I1 at their peak of upward movement will be at approximately the top orpeak of the heightened portion of cam groove 35B.

It is to be understood that the design of the cam members I8 and 35 and their grooves may be varied from the particular form herein disclosed.

In the present structure as herein disclosed, the rise and fall of the cam portion I8a are of the same degree; or in other words, the angle of this cam portion on opposite sides of the peak thereof is the same. As a result, this cam is reversible in its operation and the same thing is true of the'upper part of cam groove 35a of the return cam. Thus, the structure herein disclosed can be operated in either direction.

As will be seen from the above description, cam I8 is a single, unitary cam for actuating al1 of the plungers and this cam is also adjustable rotatably for varying the timing.

Cam 35 is also a single, unitary cam which serves to ensure return of the plungers to lower position by engagement of the inclined surface of the cam groove 35a with the plunger pins, and which also is adjustable vertically for varying the lengthof stroke of the plungers.

As above explained, the cams I8 and 35 are fixed against relative rotatable movement and thus the cam portions I8a and 35a are always maintained in proper correspondence with each other regardless of the variations in the timing and the length of stroke.

Thus, my present pump is simple and compact in its structure and arrangement of parts; it is dependable and highly eiiicient in its operation; and it can be installed as a unit with comparative ease and in the least possible and most readily available space by virtue of the general extension of this devicein an upright manner. This device can be manufactured at a reduced cost as compared with other such devices and its generally practical nature is calculated to promote the more general use of Diesel motors in the airplane as` well as automobile industry. When adapted in an airplane engine, the operating shaft will extend co-axially with respect to the cam shaft I9 instead of the arrangement herein illustrated.

Other advantages resulting from this invention will readily suggest themselves to those who are familiar with the art to which it relates.

What I claim is:

l. A fuel injection pump for a Diesel motor, comprising an oil reservoir, a plurality of reciprocatable plungers for drawing the oil therefrom and for injecting the same into the engine, a single rotatably adjustable cam for actuating the injection plungers in proper sequence and. for effecting variation in the timing of the plunger movement, a single vertically adjustable closed cam for ensuring return movement of said plungers and for varying the length of stroke of the plungers, and an operative connection for said cams.

2. A fuel injection pump for a Diesel motor, comprising an oil reservoir, a plurality of concentrically arranged and vertically disposed reciprocatable plungers for drawing the oil therefrom and injecting the same into the engine, a

single rotatably adjustable cam concentrically arranged with respect to the plungers for actuating the same in proper sequence and for effecting variation in the timing of the plunger movement, another single vertically adjustable cam concentrically arranged with respect to the plungers for ensuring return movement of said plungers and for varying the length of stroke of the plungers, an operative connection for said cams, and a single means for effecting adjustment of said cams. l

3. A fuel injection pump for a Diesel motor, comprising an oil reservoir, a plurality of concentrically arranged and vertically disposed reclprocatable plungers for drawing the oil therefrom'and injecting the same into the engine, ro-

tatably adjustable means for actuating the injection plungers in proper sequence and for varying the timing thereof, vertically adjustable means for varying the length of stroke of the plungers, and a single manipulating means for effecting adjustment of said adjustable means.

4. A fuel injection pump for a Diesel motor, comprising an oil reservoir, a plurality of concentrically arranged and vertically disposed re- 4ciprocatable plungers for drawing the oil therefrom and injecting the same into the engine, concentrically disposed cams arranged about the vertical axis of the device and having spline connection preventing relative rotative movement and causing their rotatable adjustment as a unit, one of said cams beingt operatively associated with said plungers for operation of the same and being rotatably adjustable so as to vary the timing, the other`of said cams being also operatively associated with said plungers and being vertically adjustable for varying the length of stroke of said plungers so as to vary the quantity of the oil injection and being adapted also t-o ensure return of the plungers, an operating connection for said cams, and means for simultaneously effecting said adjustments of the cams.

5. A fuel injection pump for a Diesel motor, l

comprising an oil reservoir, a plurality of concentrically arranged and vertically disposed reciprocatable plungers for drawing the oil therefrom and injecting the same into the engine, concentrically disposed cams arranged about the vertical axis of the device, one of said cams being operatively associated with said plungers for operation of the same and being adjustable for varying the timing of the plunger movement, the other of said cams being operatively associated with said plungers and being adjustable for varying the length of stroke of the plungers so as to vary the quantity of oil injection, and a single means for simultaneously effecting adjustment of said cams so as to vary the length of stroke of the plungers and their timing, said adjusting means including a metering cam arranged concentrically with respect to the plungers, and a vertically disposed and concentrically arranged rod operatively connected to said first-named cams, and means for manipulating said adjusting means, and a concentrically arranged op erating connection for said cams.

6. A fuel injection pump for a Diesel motor, comprising an oil reservoir, a plurality of concentrically arranged and vertically disposed reciprocatable plungers for drawing the oil therefrom and injecting the same into the engine, concentrically disposed cams arranged about the vertical axis of the device, one of said cams being operatively associated with said plungers for operation of the same and being rotatably adjustable for varying the timing of the plunger movement, the other of said cams being operatively associated with said plungers and being longitudinally adjustable for varying the length of stroke of the plungers so as to vary the quantity of oil injection, a concentrically arranged hollow operating shaft for said cams, and a single means for simultaneously effecting adjustment of said cams so as to vary the length of stroke of the plungers and their timing, said adjusting means including a rod concentrically disposed Within said operating shaft, a metering cam slot and pin mechanism at the upper end of said rod for manipulating the same, and cam slot and pin mechanism at the lower end of said rod for transmitting such adjustment to said rst named cams, and an operating connection for said cams.' 

